67 resultados para Vegetação


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Availability of good quality water has been reduced vertiginously, over the last decade, in the world. In some regions, the water resources have high concentration of the dissolved salts, these characteristics of the water make it s use impossible. Water quality can be a limitation for irrigated agriculture, principally in regions of arid or semiarid climate where the water resources are generally saline and are exposed at high evaporation ratio. For that reason, precipitation of the salts occurs near the soil surface and those salts themselves cumulate in the vegetal tissue, reducing the soil fertility and crop production. The adoption of tolerant crop to the water salinity and soil salinity, adaptable to the climatic conditions is other emergent necessity. This work had the goal of studying the effects of four salinity levels of the irrigation water salinity and use of mulch, dried leaves of Forest mangrove (Acacia mangiumWilld), in cultivated soil with amaranth (Amaranthus cruentus, BRS Alegria variety), in greenhouse. It was utilized the transplant of plants to PVC columns, containing 30 kg of silty loam soil, 10 days after emerging, with space of 50 x 50 cm between lines. Treatments were composed by combination of four levels of salinity (0.147; 1.500; 3.000 e 4.500 dS m-1), obtained by addition NaCl (commercial) to irrigation water and soil with and without protection, by mulch. A factorial system 4 x 2 was used with four repetitions, totalizing 32 parcels. The concentrations of nutrients in soil solution have been evaluated, in the dry matter of the vegetal tissue (roots, stem, leaves and raceme residue), at the end of the vegetative cycle. The use of soil protection reduced time for the beginning inflorescence of plants, at the same time, the increase of the salinity delayed this phase of amaranth development. The use of the mulch effectively increased the height, stem diameter, area of the larger leaf, humidity and dry matter content and amaranth grain production. The vegetal species showed salinity tolerance to experimented levels. The adopted treatments did not affect the pH values, exchangeable cation contents, electrical conductivity of soil solution (EC1:5) and saturated extract (ECSE), and Ca+2, Mg+, Fe+2 and Mn+2 contents, in the soil solution. The increase of the salinity concentration in the irrigation water inhibited the mineralization process of the organic matter (OM) and, consequently, the efficiency in the it´s utilization by plants, at the same time, produced increase in the values of the exchangeable sodium percentage (ESP), sodium adsorption ratio (SAR) and potassium adsorption ratio (PAR), in the soil solution. Therefore, the use of the mulch did not affect the first three parameters. The protein and nutrient contents: K+, Ca+2, P, Mg+2 e Cu+2, in amaranth grains, were improved by tillage condition. The raceme residues showed chemical/nutritional composition that makes advantageous its application in animal ration. In this context, it follows that amaranth tolerate the saline stress, of the irrigation water, until 4.500 dS m-1, temperature and relative humidity of the air predominant in the experimental environment

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The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

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Due to the increasing activities and its disordered occupation, the catchment of the Pitimbu river is reason of concern for the population, since the river empties in the lagoon of the Jiqui where 30% of the water of this lagoon are caught for the supplying the city of Natal, playing an important fuction in the supply of water superficial for the capital of the Rio Grande do Norte. The superior stretch of the hydrography catchment of the Pitimbu river - Macaíba/RN, object of this study, is denoted by the eminently agricultural occupation with the use of the irrigated agriculture in the many properties that compose this stretch. Because of this becomes necessary to analyze the availability of the water resources in the catchment of the Pitimbu river, in the superior stretch, collating with the use and occupation of the existing terrain. The stretch in study was divided in eight points which had been performed tests throughout the water and analyzed the parameters physicist-chemistries and heavy metals that are praised by resolution CONAMA nº 357 e, visits in field with photographic survey for characterization of this verifying the situation where if it finds the river. The stretch presented some divergence in the parameters of pH and iron, however the results denote a characteristic of the region. The great amount of slide barrages throughout the river and the wet street was observed, had also verified near the edges the launching of garbage and, the great amount of aquatic vegetation. With this it is concluded that the water of the river can be used for human supplying, therefore inside presents a quality of drinking waters of the standards demanded for resolution CONAMA nº 357, in this way, the stretch in study could be adopted as an Envoiremental Area Protection (APA), to preserve and to guarantee, at least in this stretch, that its condition remains unchanged and continues to supply of permanent form a water of excellent quality

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In northeastern semiarid, seasonality on precipitation temporal distribution, high intensity storm events and inadequate management of native vegetation can promote soil erosion. Vegetation removal causes soil surface exposure, reduces soil water storage capacity and can be the source degradation processes. In this context, this approach aims to analyze water and soil erosion processes on a 250 m2 undisturbed experimental plot with native vegetation, slope 2.5% by using 2006 and 2007 monitoring data. The site was instrumented to monitor rainfall, overland flow runoff and erosion by using a 5 m³ tank downstream the plot. Soil erosion monitoring was made by transported sediment and organic matter collection after each event. Field infiltration experiments were made at 16 points randomly distributed within the plot area by using a constant head infiltrometer during drought and rainy seasons, respectively. Infiltration data revealed high spatial and temporal variability. It was observed that during the beginning of the rainy period, 77% of the events showed runoff coefficient less than 0.05. As the rainy season began, soil water increase produced annual species germination. High intensity storms resulted in runoff coefficients varying between 0.33 and 0.42. Once the annual species was established, it was observed that approximately 39% of the events produced no runoff, which reflects an increase on soil water retention capacity caused by the vegetation. A gradual runoff reduction during the rainy season emphasizes the effect of vegetative density increase. Soil erosion observed data allowed to fit an empirical relationship involving soil loss and precipitation height, which was used to analyze the plot installation impact on soil erosion. Observed soil loss in 2006 and 2007 was 230 Kg/ha and 54 Kg/ha, respectively

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The city of Natal-RN is constructed on dune areas with wavy relives softly waved and green areas that help to keep a pleasant climate, amongst these is distinguished field Pirangi-Potengi the dune with the areas of San Vale and Lagoinha. These environments are being substituted gradual for property and other workmanships of engineering on behalf of the urban expansion. This study the elaboration of a geoambiental mapping of Field had as objective generality Pirangi-Potengi the Dune with emphasis the San Vale and Lagoinha in Natal-RN. The done mapping had as objective specific to elaborate a vegetation map, a map of registers in cadastre of ambient problems to dunes, a map of flooding susceptibility, a map of vulnerability to the underground water contamination and a map of use and occupation of the ground. Of the carried through analysis, the area in study reveals sufficiently degraded, remaining only few green areas and dunares, as well as, the vulnerable presence of areas of vulnerability in floods and areas the contamination of the water-bearing one. The gotten results allow to affirm that this type of mapping, is of great importance for analysis and evaluation of the environment of the city

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Through out the course of a steady increase in search and recovery of space in the coastal zone, there is also an expanding concern about the erosion processes of this area. The main problem in coastal areas is that urbanization occurs in a disorderly fashion and unsustainable, further aggravating the problems of coastal dynamics. The study area of this work is located on the southern coast of Pirangi do Norte beach to about 20km south of Natal, capital of Rio Grande do Norte in the Parnamirim City. This area has the length of approximately 1km, divided into three sections (Western, Central and Eastern) with a morphology consisting of a tableland at the top, sea cliffs in the West and Central parts and sand dunes in the Eastern section, both vegetated, and a coastal plain on the inferior part associated with the presence of beach rocks. This study aimed to analyze the erosion processes operating in the excerpt of Pirangi do Norte beach and assess the feasibility of their monitoring making use of DGPS (Global Positioning System Differential mode). During the work it was carried out a physical description of the area through photo-interpretation and site survey after measurement of the shoreline in the period between November 2004 and November 2009 and beach profiles between August 2005 and July 2006. The analysis of the results of the annual surveys showed the occurrence of variations of the shoreline along the stretch traveled. Sites are identified in advancement coast from the sea and it was verified in loco the presence of erosion with deposition of materials on the lower part of the coastal bluff, the former position of the shoreline, showing a false notion of advancing it. This leads to the conclusion that the data collected in a survey of the shoreline should always be accompanied by photographic records of the local area and with the highest rate of erosion, thus avoiding the mistake of treating the deposit materials as evidence of progress coast. At the end of the study, after a review of various works to mitigate the erosion in the coastal zone, it is recommended to the area of study the adoption of an artificial feeding of the beach, aiming the minimization of the erosive effects of the tides. Moreover, it is suggested that even the continuity of monitoring, maintenance of existing vegetation and control of the occupation on the edge of sea cliffs

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In the semiarid region of northeastern of Brazil, the reservoirs are vulnerable to water level seasonal fluctuations, they re related to the hydrological cycle. The rain periods are irregular and there are long periods of drought that increases eutrophication process. That happens because of the water level s reduction and nutrient concentration. The Boqueirao, located in northeastern Brazil , is a mesotrophic reservoir. The reservoir is naturally susceptible to deterioration of water quality. This happens because of the potential diffuse sources arising from the use and occupation of the basin, associated with shallow soil caatinga biome and highly vulnerable to erosion. This study aimed to analyze the influence of the use and occupation of the area around and the water quality of the watershed. A study of the area around the Boqueirão was performed, taking the potentially polluting activities. Limnological variables were monitored monthly in 3 points of the reservoir to assess the water quality. Was evidenced an event of prolonged drought, with rainfall below the historical average for the year of study. By the index of water quality, the watershed was classified as " good " during the whole year of 2012. According to the trophic index adopted the reservoir is characterized as mesotrophic. The main anthropogenic impacts identified in the soil were arboreal selective logging, mining, diffuse contribution of residues from agricultural and livestock activities. The lack of precipitation and the degradation of the surrounding area, affect negatively the water quality, requiring immediate control to prevent degradation of the watershed . Although there wasn t a majority polluting activity in the region. The total of several impacting activities, the high susceptibility of the soil and the selective clearing of caatinga vegetation can accelerate the natural process of eutrophication in the water body

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The present work objective to study the configurations that the hinterland it acquires in the workmanship Great hinterland: trails, of Guimarães Rosa demonstrating as this author humanize this element, conferring to it characters universal mystics and through investigations, uncertainties, the auto-corrections of Riobaldo that become hinterland a metaphor of the human interior. Three are the chapters, that they will guide this work: the chapter 1 presents as element key for characterization of the epic one in Great hinterland: trails, the mining hinterland replete of trails, palco of exuberant vegetation, huge and multidimensional scene, where it has an entrecruzamento of fiction and reality. It retakes quarrel of critics as Manuel Cavalcanti Proença, Roberto Schwarz, on the existing epic character in the Great hinterland: trails, constructed from deriving myths of the universal culture, that they had been become popular. The brave and gracious knight, that it has its representabilidade in the popular culture. Thus the medieval hero, the knight represented for the Riobaldo personage, it is cognominado by Proença as Don Riobaldo of the Urucuia, knight of the general fields. O chapter 2 is a study on the popular culture in Rosa and Cascudo. Cascudo the example of Rosa also is exímio studious of the brazilian life, the regionalization and the popular manifestations proceeding from other cultures. O chapter 3 it has as focus of analysis two mitopoéticas personages: Diadorim e Luzia-Homem, which in the cited narratives they generally they assume functions generally atribute the men. Since children, if they dresses male. Valley to point out that Diadorim is not characterized as man, since in Great hinterland:trails if trajaq always as gunman. Luzia, when complete 18 anos pass if to dress as woman, but the stigma of male and female, inherited of the time where it coexisted the father folloies it for all the life. They suffer pain to have been born to fight and to não conhecer to love. They die you deliver the God. This study detects exactly that Diadorim and Luzia-Homem, are personages associates the myths of the universal culture and popular (sphinx, Jellyfish, Venus, Mother d water), that they possess similarities n the archetypes, that transit between the sexos masculine and feminine, without any sexual connotation, possesss it proper code of honr, of this not abdicating ahead of the death. Parallel, in this chapter two cascudianas workmanships willbe studies, that contemplate thematic of the dressed woman of man and being the woman without disguice: the enchantment tale Maria Gomes and romance Flower of tragics romances. The first one will be revisited in order to present subject in Great hinterland:trails through the Diadorim personage. As it will discourse on cases of brave women, cited for Cascudo, immortalized for the tradition, who had made history, that already is not disfarçam of men to carry through acts of bravery and honor.

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The objective of this work is to identify, to chart and to explain the evolution of the soil occupation and the envirionment vulnerability of the areas of Canto do Amaro and Alto da Pedra, in the city of Mossoró-RN, having as base analyzes it multiweather of images of orbital remote sensors, the accomplishment of extensive integrated works of field to a Geographic Information System (GIS). With the use of inserted techniques of it analyzes space inserted in a (GIS), and related with the interpretation and analyzes of products that comes from the Remote Sensoriamento (RS.), make possible resulted significant to reach the objectives of this works. Having as support for the management of the information, the data set gotten of the most varied sources and stored in digital environment, it comes to constitute the geographic data base of this research. The previous knowledge of the spectral behavior of the natural or artificial targets, and the use of algorithms of Processing of Digital images (DIP), it facilitates the interpretation task sufficiently and searchs of new information on the spectral level. Use as background these data, was generated a varied thematic cartography was: Maps of Geology, Geomorfológicals Units soils, Vegetation and Use and Occupation of the soil. The crossing in environment SIG, of the above-mentioned maps, generated the maps of Natural and Vulnerability envirionmental of the petroliferous fields of I Canto do Amaro and Alto da Pedra-RN, working in an ambient centered in the management of waters and solid residuos, as well as the analysis of the spatial data, making possible then a more complex analysis of the studied area

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Among placental mammals, primates are the only ones to present trichromatic color vision. However, the distribution of trichromacy among primates is not homogeneous: Old World primates shows an uniform trichromacy (with all individuals being trichromats) and New World primates exhibit a color vision polymorphism (with dichromatic males and dichromatic or trichromatic females). Visual ecology studies have investigated which selective pressures may have been responsible for the evolution of trichromacy in primates, diverging from the dichromat standard found in other mammals. Cues associated with foraging and the socio-reproductive status were analyzed, indicating a trichromatic advantage for the rapid detection of visually conspicuous objects against a green background. However, dichromats are characterized by an efficient capture of cryptic and camouflaged stimuli. These advantages regarding phenotype may be responsible for the maintenance of the visual polymorphism in New World primates and for the high incidence of color blindness in humans (standing around 8% in Caucasian men). An important factor that has not yet been experimentally taken into account is the predation risk and its effect on the evolution of trichromacy in primates. To answer this question, we prepared and edited pictures of animals with different coats: oncillas (Leopardus spp.), puma (Puma concolor) and ferret (Galictis cuja). The specimens were taxidermized and the photographs were taken in three different vegetation scenarios (dense forest, cerrado and grassland). The images of the predators were manipulated so that they fit into two categories of stimulus size (small or large). After color calibration and photo editing, these were presented to 40 humans (20 dichromats and 20 trichromats) by a computer program, which presented a set of four photos at a time (one picture containing the taxidermized animal amid the background vegetation and three depicting only the background vegetation) and recorded the response latency and success rate of the subjects. The results show a trichromatic advantage in detecting potential predators. The predator detection was influenced by the background, the predator species, the dimension of the stimulus and the observer s visual phenotype. As humans have a high rate of dyschromatopsias, when compared to wild Catarrhini or human tribal populations, it is possible that the increased rate of dichromats is a result of reduced pressure for rapid predator detection. Since our species came to live in more cohesive groups and resistant to attack by predators, with the advent of agriculture and the formation of villages, it is possible that the lower risk of predation has reduced the selection in favor of trichromats

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Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region

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Collembola is one of the most abundant and diverse group of terrestrial arthropods, being at the base of the food chain operating in the decomposition process. They have a wide distribution in the world and can be found in practically all habitats. The knowledge of this distinctive fauna is still deficient in brazilian territory, especially in semi-arid region. The aim of this study was to investigate which climatic variables may act as predictors of species richness, abundance of individuals and compositional structure of the taxocenose of Collembola over 12 months in an area dominated by semi-arid Caatinga vegetation, northeastern Brazil and describe new species of the genus Seira found, more diverse taxon of Collembola in Brazil. Samples were collected in João Câmara, Rio Grande do Norte. Ten plots of 20 x 20 meters were established and the specimens were collected with collection effort of one hour/people using entomological aspirator. The identification and description of the species was carried out by studying the morphology and chaetotaxy. Was performed a multiple regression analysis between species richness and abundance of individuals with climatic variables. A total of 1231 individuals belonging to 15 species, 12 genera and nine families. The greatest richness and abundance of Collembola were found during the rainy season. The genus Seira was the most abundant. Rainfall explained the temporal variation in species richness and abundance of Collembola in the semi-arid region, which is consistent with the biology of these animals. The populations of Collembola showed grouped distribution. Three new species of Seira were described and illustrated and all show similarities with species already registered in the national territory

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The municipality of Guamaré is located on the north coast of RN, Salineira zone, with a land area of 259 km2 and a population of approximately 12,500 inhabitants (IBGE, 2010). Presents strong morphological instability caused mainly by the influence of human activities in the region. The present study aims to assess the existing levels of salts in the springs of the region, by evaluating the electrical conductivity, pH, salinity, chlorides, hardness, calcium, magnesium and heavy metals in the water. The collection and analysis methods adopted in the survey are based on APHA (2005). The electrical conductivity, salinity and chloride behaved similarly throughout the study. Some points suffered the direct effect of the salt ponds and others. Given the existence of a drainage ditch between the saline and monitored region, there was little change in the environment, including the native vegetation. The opposite situation occurred in farms where the region is fully committed local vegetation and water holes and wells used in the past for domestic use are practically disabled (high salt content). In Rio Miassaba formation of an estuary is reversed, with the farther out from the sea showing higher salt concentracions, which may be associated with the discharge of organic matter and natural evaporation rate. In periods of no rainfall had a few points higher than the levels of salts found in seawater and may be associated with high evaporation in the region. Detected a positive factor is the high resilience and reducing salt, after periods of rainfall incidence

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Fungi of the family Nidulariaceae or bird s nest fungi present a vase-shaped basidiomata with the wall surface smooth or striated lengthwise and internal structures resembling small bird eggs in a nest, the peridioles. Among the five genera that comprise the group, the more representative is Cyathus Haller: Pers. The Brazilian Northeast region shows major importance for the world s diversity by containing a Brazilian unique and exclusively phytoecological domain, the Caatinga, which lacks particular attention regarding macrofungi. Although the gradual growth of knowledge in recent years, studies are still insipient in the Caatinga domain. Between their various vegetal formations are the Brejos de Altitude , described as islands with moist perennial vegetation, low soil fertility and annual precipitation of 900 1.300 mm. This study aimed to evaluate the taxonomic richness of Nidulariaceae fungi in Caatinga s areas of Northeastern Brazil, describing and identifying species, as well as expanding the collection of Herbarium UFRN Fungos. For description of Nidulariaceae fungi was followed the proposed by specialized literature in the group. We have found and described 10 species of the genus Cyathus, namely: C. earlei Lloyd, C. gayanus Tul. & C. Tul., C. gracilis H.J. Brodie, C. intermedius (Mont.) Tul. & C. Tul., C. limbatus Tul. & C. Tul., C. montagnei Tul. & C. Tul., C. pallidus Berk. & M.A. Curtis, C. poeppigii Tul. & C. Tul., C. striatus (Huds.) Willd. and C. tríplex Lloyd. Beyond these have been described four new species to science: Cyathus calvescens R. Cruz & Baseia sp. nov., C. hortum R. Cruz & Baseia sp. nov., C. magnomuralis R. Cruz & Baseia sp. nov. and C. parvocinereus R. Cruz & Baseia sp. nov. Two samples were identified only to genus level. No member of Mycocalia J.T. Palmer, Nidula V.S. White, Nidularia Fr. and Crucibulum Tul. & C. Tul. has been found, however the results were extremely valuable for being an unprecedented work in Caatinga, and importante tool for implementation of conservation projects and sustainable utilization of this domain

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Arbuscular mycorrhizal fungi (AMF) are obligatory symbiotic organisms that associate with roots of a large number of plant taxa, and are found in all terrestrial ecosystems. These fungi promote greater tolerance to environmental stresses to associated plant, favoring the establishment of plant communities, especially where soil fertility is a limiting factor, as in the Caatinga, an exclusively Brazilian domain that has been focus of research due to its great biodiversity that can help clarify the history of vegetation in South America. Because of the ecological importance of AMF, the limited number of jobs and the potential diversity of the Caatinga, this work aims to inventory the diversity and determine AMF communities in areas with different faces occurrent in FLONA Araripe, Ceará (CE). The sample collection occurred in four periods at the beginning and end of the dry season (August and December 2011, respectively) and rainy (February and June 2012, respectively) in an area of marsh and woodland altitude of the Araripe, Crato, CE. The glomerosporos were extracted by wet sieving and centrifugation in water and sucrose (50%) mounted between slide and coverslip using PVLG and PVLG + Reagent Melzer. In total, we found 46 species of AMF distributed in eight families and 16 genera: Acaulospora (6), Ambispora (1), Cetraspora (2), Dentiscutata (5), Fuscutata (2), Gigaspora (6), Glomus (13) Intraornatospora (1), Kuklospora (1), Orbispora (1), Paradentiscutata (1), Quatunica (1), Racocetra (1), Scutellospora (2), Septoglomus (2) and a new genus. analysis showed that ecological each area of study has its own seasonal dynamics, with an area of woodland with a greater diversity of species throughout the year, while the marsh elevation showed greater variation in species found among the collection periods, showing that vegetation and rainfall has strong influence on the seasonal dynamics of AMF, as well as the availability of nutrients and soil pH so